/* Low-level child interface to ttrace. Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc. This file is part of GDB. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ #include "defs.h" /* The ttrace(2) system call didn't exist before HP-UX 10.30. Don't try to compile this code unless we have it. */ #ifdef HAVE_TTRACE #include "command.h" #include "gdbcore.h" #include "gdbthread.h" #include "inferior.h" #include "target.h" #include "gdb_assert.h" #include "gdb_string.h" #include #include #include #include "inf-child.h" #include "inf-ttrace.h" /* HACK: Save the ttrace ops returned by inf_ttrace_target. */ static struct target_ops *ttrace_ops_hack; /* HP-UX uses a threading model where each user-space thread corresponds to a kernel thread. These kernel threads are called lwps. The ttrace(2) interface gives us almost full control over the threads, which makes it very easy to support them in GDB. We identify the threads by process ID and lwp ID. The ttrace(2) also provides us with a thread's user ID (in the `tts_user_tid' member of `ttstate_t') but we don't use that (yet) as it isn't necessary to uniquely label the thread. */ /* Number of active lwps. */ static int inf_ttrace_num_lwps; /* On HP-UX versions that have the ttrace(2) system call, we can implement "hardware" watchpoints by fiddling with the protection of pages in the address space that contain the variable being watched. In order to implement this, we keep a dictionary of pages for which we have changed the protection. */ struct inf_ttrace_page { CORE_ADDR addr; /* Page address. */ int prot; /* Protection. */ int refcount; /* Reference count. */ struct inf_ttrace_page *next; struct inf_ttrace_page *prev; }; struct inf_ttrace_page_dict { struct inf_ttrace_page buckets[128]; int pagesize; /* Page size. */ int count; /* Number of pages in this dictionary. */ } inf_ttrace_page_dict; struct inf_ttrace_private_thread_info { int dying; }; /* Number of lwps that are currently in a system call. */ static int inf_ttrace_num_lwps_in_syscall; /* Flag to indicate whether we should re-enable page protections after the next wait. */ static int inf_ttrace_reenable_page_protections; /* Enable system call events for process PID. */ static void inf_ttrace_enable_syscall_events (pid_t pid) { ttevent_t tte; ttstate_t tts; gdb_assert (inf_ttrace_num_lwps_in_syscall == 0); if (ttrace (TT_PROC_GET_EVENT_MASK, pid, 0, (uintptr_t)&tte, sizeof tte, 0) == -1) perror_with_name (("ttrace")); tte.tte_events |= (TTEVT_SYSCALL_ENTRY | TTEVT_SYSCALL_RETURN); if (ttrace (TT_PROC_SET_EVENT_MASK, pid, 0, (uintptr_t)&tte, sizeof tte, 0) == -1) perror_with_name (("ttrace")); if (ttrace (TT_PROC_GET_FIRST_LWP_STATE, pid, 0, (uintptr_t)&tts, sizeof tts, 0) == -1) perror_with_name (("ttrace")); if (tts.tts_flags & TTS_INSYSCALL) inf_ttrace_num_lwps_in_syscall++; /* FIXME: Handle multiple threads. */ } /* Disable system call events for process PID. */ static void inf_ttrace_disable_syscall_events (pid_t pid) { ttevent_t tte; gdb_assert (inf_ttrace_page_dict.count == 0); if (ttrace (TT_PROC_GET_EVENT_MASK, pid, 0, (uintptr_t)&tte, sizeof tte, 0) == -1) perror_with_name (("ttrace")); tte.tte_events &= ~(TTEVT_SYSCALL_ENTRY | TTEVT_SYSCALL_RETURN); if (ttrace (TT_PROC_SET_EVENT_MASK, pid, 0, (uintptr_t)&tte, sizeof tte, 0) == -1) perror_with_name (("ttrace")); inf_ttrace_num_lwps_in_syscall = 0; } /* Get information about the page at address ADDR for process PID from the dictionary. */ static struct inf_ttrace_page * inf_ttrace_get_page (pid_t pid, CORE_ADDR addr) { const int num_buckets = ARRAY_SIZE (inf_ttrace_page_dict.buckets); const int pagesize = inf_ttrace_page_dict.pagesize; int bucket; struct inf_ttrace_page *page; bucket = (addr / pagesize) % num_buckets; page = &inf_ttrace_page_dict.buckets[bucket]; while (page) { if (page->addr == addr) break; page = page->next; } return page; } /* Add the page at address ADDR for process PID to the dictionary. */ static struct inf_ttrace_page * inf_ttrace_add_page (pid_t pid, CORE_ADDR addr) { const int num_buckets = ARRAY_SIZE (inf_ttrace_page_dict.buckets); const int pagesize = inf_ttrace_page_dict.pagesize; int bucket; struct inf_ttrace_page *page; struct inf_ttrace_page *prev = NULL; bucket = (addr / pagesize) % num_buckets; page = &inf_ttrace_page_dict.buckets[bucket]; while (page) { if (page->addr == addr) break; prev = page; page = page->next; } if (!page) { int prot; if (ttrace (TT_PROC_GET_MPROTECT, pid, 0, addr, 0, (uintptr_t)&prot) == -1) perror_with_name (("ttrace")); page = XMALLOC (struct inf_ttrace_page); page->addr = addr; page->prot = prot; page->refcount = 0; page->next = NULL; page->prev = prev; prev->next = page; inf_ttrace_page_dict.count++; if (inf_ttrace_page_dict.count == 1) inf_ttrace_enable_syscall_events (pid); if (inf_ttrace_num_lwps_in_syscall == 0) { if (ttrace (TT_PROC_SET_MPROTECT, pid, 0, addr, pagesize, prot & ~PROT_WRITE) == -1) perror_with_name (("ttrace")); } } return page; } /* Insert the page at address ADDR of process PID to the dictionary. */ static void inf_ttrace_insert_page (pid_t pid, CORE_ADDR addr) { struct inf_ttrace_page *page; page = inf_ttrace_get_page (pid, addr); if (!page) page = inf_ttrace_add_page (pid, addr); page->refcount++; } /* Remove the page at address ADDR of process PID from the dictionary. */ static void inf_ttrace_remove_page (pid_t pid, CORE_ADDR addr) { const int pagesize = inf_ttrace_page_dict.pagesize; struct inf_ttrace_page *page; page = inf_ttrace_get_page (pid, addr); page->refcount--; gdb_assert (page->refcount >= 0); if (page->refcount == 0) { if (inf_ttrace_num_lwps_in_syscall == 0) { if (ttrace (TT_PROC_SET_MPROTECT, pid, 0, addr, pagesize, page->prot) == -1) perror_with_name (("ttrace")); } inf_ttrace_page_dict.count--; if (inf_ttrace_page_dict.count == 0) inf_ttrace_disable_syscall_events (pid); page->prev->next = page->next; if (page->next) page->next->prev = page->prev; xfree (page); } } /* Mask the bits in PROT from the page protections that are currently in the dictionary for process PID. */ static void inf_ttrace_mask_page_protections (pid_t pid, int prot) { const int num_buckets = ARRAY_SIZE (inf_ttrace_page_dict.buckets); const int pagesize = inf_ttrace_page_dict.pagesize; int bucket; for (bucket = 0; bucket < num_buckets; bucket++) { struct inf_ttrace_page *page; page = inf_ttrace_page_dict.buckets[bucket].next; while (page) { if (ttrace (TT_PROC_SET_MPROTECT, pid, 0, page->addr, pagesize, page->prot & ~prot) == -1) perror_with_name (("ttrace")); page = page->next; } } } /* Write-protect the pages in the dictionary for process PID. */ static void inf_ttrace_enable_page_protections (pid_t pid) { inf_ttrace_mask_page_protections (pid, PROT_WRITE); } /* Restore the protection of the pages in the dictionary for process PID. */ static void inf_ttrace_disable_page_protections (pid_t pid) { inf_ttrace_mask_page_protections (pid, 0); } /* Insert a "hardware" watchpoint for LEN bytes at address ADDR of type TYPE. */ static int inf_ttrace_insert_watchpoint (CORE_ADDR addr, int len, int type) { const int pagesize = inf_ttrace_page_dict.pagesize; pid_t pid = ptid_get_pid (inferior_ptid); CORE_ADDR page_addr; int num_pages; int page; gdb_assert (type == hw_write); page_addr = (addr / pagesize) * pagesize; num_pages = (len + pagesize - 1) / pagesize; for (page = 0; page < num_pages; page++, page_addr += pagesize) inf_ttrace_insert_page (pid, page_addr); return 1; } /* Remove a "hardware" watchpoint for LEN bytes at address ADDR of type TYPE. */ static int inf_ttrace_remove_watchpoint (CORE_ADDR addr, int len, int type) { const int pagesize = inf_ttrace_page_dict.pagesize; pid_t pid = ptid_get_pid (inferior_ptid); CORE_ADDR page_addr; int num_pages; int page; gdb_assert (type == hw_write); page_addr = (addr / pagesize) * pagesize; num_pages = (len + pagesize - 1) / pagesize; for (page = 0; page < num_pages; page++, page_addr += pagesize) inf_ttrace_remove_page (pid, page_addr); return 1; } static int inf_ttrace_can_use_hw_breakpoint (int type, int len, int ot) { return (type == bp_hardware_watchpoint); } static int inf_ttrace_region_ok_for_hw_watchpoint (CORE_ADDR addr, int len) { return 1; } /* Return non-zero if the current inferior was (potentially) stopped by hitting a "hardware" watchpoint. */ static int inf_ttrace_stopped_by_watchpoint (void) { pid_t pid = ptid_get_pid (inferior_ptid); lwpid_t lwpid = ptid_get_lwp (inferior_ptid); ttstate_t tts; if (inf_ttrace_page_dict.count > 0) { if (ttrace (TT_LWP_GET_STATE, pid, lwpid, (uintptr_t)&tts, sizeof tts, 0) == -1) perror_with_name (("ttrace")); if (tts.tts_event == TTEVT_SIGNAL && tts.tts_u.tts_signal.tts_signo == SIGBUS) { const int pagesize = inf_ttrace_page_dict.pagesize; void *addr = tts.tts_u.tts_signal.tts_siginfo.si_addr; CORE_ADDR page_addr = ((uintptr_t)addr / pagesize) * pagesize; if (inf_ttrace_get_page (pid, page_addr)) return 1; } } return 0; } /* When tracking a vfork(2), we cannot detach from the parent until after the child has called exec(3) or has exited. If we are still attached to the parent, this variable will be set to the process ID of the parent. Otherwise it will be set to zero. */ static pid_t inf_ttrace_vfork_ppid = -1; static int inf_ttrace_follow_fork (struct target_ops *ops, int follow_child) { pid_t pid, fpid; lwpid_t lwpid, flwpid; ttstate_t tts; struct thread_info *last_tp = NULL; struct breakpoint *step_resume_breakpoint = NULL; CORE_ADDR step_range_start = 0, step_range_end = 0; struct frame_id step_frame_id = null_frame_id; /* FIXME: kettenis/20050720: This stuff should really be passed as an argument by our caller. */ { ptid_t ptid; struct target_waitstatus status; get_last_target_status (&ptid, &status); gdb_assert (status.kind == TARGET_WAITKIND_FORKED || status.kind == TARGET_WAITKIND_VFORKED); pid = ptid_get_pid (ptid); lwpid = ptid_get_lwp (ptid); last_tp = find_thread_pid (ptid); } /* Get all important details that core GDB doesn't (and shouldn't) know about. */ if (ttrace (TT_LWP_GET_STATE, pid, lwpid, (uintptr_t)&tts, sizeof tts, 0) == -1) perror_with_name (("ttrace")); gdb_assert (tts.tts_event == TTEVT_FORK || tts.tts_event == TTEVT_VFORK); if (tts.tts_u.tts_fork.tts_isparent) { pid = tts.tts_pid; lwpid = tts.tts_lwpid; fpid = tts.tts_u.tts_fork.tts_fpid; flwpid = tts.tts_u.tts_fork.tts_flwpid; } else { pid = tts.tts_u.tts_fork.tts_fpid; lwpid = tts.tts_u.tts_fork.tts_flwpid; fpid = tts.tts_pid; flwpid = tts.tts_lwpid; } if (follow_child) { /* Copy user stepping state to the new inferior thread. */ step_resume_breakpoint = last_tp->step_resume_breakpoint; step_range_start = last_tp->step_range_start; step_range_end = last_tp->step_range_end; step_frame_id = last_tp->step_frame_id; /* Otherwise, deleting the parent would get rid of this breakpoint. */ last_tp->step_resume_breakpoint = NULL; inferior_ptid = ptid_build (fpid, flwpid, 0); add_inferior (fpid); detach_breakpoints (pid); target_terminal_ours (); fprintf_unfiltered (gdb_stdlog, _("\ Attaching after fork to child process %ld.\n"), (long)fpid); } else { inferior_ptid = ptid_build (pid, lwpid, 0); detach_breakpoints (fpid); target_terminal_ours (); fprintf_unfiltered (gdb_stdlog, _("\ Detaching after fork from child process %ld.\n"), (long)fpid); } if (tts.tts_event == TTEVT_VFORK) { gdb_assert (!tts.tts_u.tts_fork.tts_isparent); if (follow_child) { /* We can't detach from the parent yet. */ inf_ttrace_vfork_ppid = pid; reattach_breakpoints (fpid); } else { if (ttrace (TT_PROC_DETACH, fpid, 0, 0, 0, 0) == -1) perror_with_name (("ttrace")); /* Wait till we get the TTEVT_VFORK event in the parent. This indicates that the child has called exec(3) or has exited and that the parent is ready to be traced again. */ if (ttrace_wait (pid, lwpid, TTRACE_WAITOK, &tts, sizeof tts) == -1) perror_with_name (("ttrace_wait")); gdb_assert (tts.tts_event == TTEVT_VFORK); gdb_assert (tts.tts_u.tts_fork.tts_isparent); reattach_breakpoints (pid); } } else { gdb_assert (tts.tts_u.tts_fork.tts_isparent); if (follow_child) { if (ttrace (TT_PROC_DETACH, pid, 0, 0, 0, 0) == -1) perror_with_name (("ttrace")); } else { if (ttrace (TT_PROC_DETACH, fpid, 0, 0, 0, 0) == -1) perror_with_name (("ttrace")); } } if (follow_child) { struct thread_info *ti; /* The child will start out single-threaded. */ inf_ttrace_num_lwps = 1; inf_ttrace_num_lwps_in_syscall = 0; /* Delete parent. */ delete_thread_silent (ptid_build (pid, lwpid, 0)); detach_inferior (pid); /* Add child thread. inferior_ptid was already set above. */ ti = add_thread_silent (inferior_ptid); ti->private = xmalloc (sizeof (struct inf_ttrace_private_thread_info)); memset (ti->private, 0, sizeof (struct inf_ttrace_private_thread_info)); ti->step_resume_breakpoint = step_resume_breakpoint; ti->step_range_start = step_range_start; ti->step_range_end = step_range_end; ti->step_frame_id = step_frame_id; /* Reset breakpoints in the child as appropriate. */ follow_inferior_reset_breakpoints (); } return 0; } /* File descriptors for pipes used as semaphores during initial startup of an inferior. */ static int inf_ttrace_pfd1[2]; static int inf_ttrace_pfd2[2]; static void do_cleanup_pfds (void *dummy) { close (inf_ttrace_pfd1[0]); close (inf_ttrace_pfd1[1]); close (inf_ttrace_pfd2[0]); close (inf_ttrace_pfd2[1]); } static void inf_ttrace_prepare (void) { if (pipe (inf_ttrace_pfd1) == -1) perror_with_name (("pipe")); if (pipe (inf_ttrace_pfd2) == -1) { close (inf_ttrace_pfd1[0]); close (inf_ttrace_pfd2[0]); perror_with_name (("pipe")); } } /* Prepare to be traced. */ static void inf_ttrace_me (void) { struct cleanup *old_chain = make_cleanup (do_cleanup_pfds, 0); char c; /* "Trace me, Dr. Memory!" */ if (ttrace (TT_PROC_SETTRC, 0, 0, 0, TT_VERSION, 0) == -1) perror_with_name (("ttrace")); /* Tell our parent that we are ready to be traced. */ if (write (inf_ttrace_pfd1[1], &c, sizeof c) != sizeof c) perror_with_name (("write")); /* Wait until our parent has set the initial event mask. */ if (read (inf_ttrace_pfd2[0], &c, sizeof c) != sizeof c) perror_with_name (("read")); do_cleanups (old_chain); } /* Start tracing PID. */ static void inf_ttrace_him (int pid) { struct cleanup *old_chain = make_cleanup (do_cleanup_pfds, 0); ttevent_t tte; char c; /* Wait until our child is ready to be traced. */ if (read (inf_ttrace_pfd1[0], &c, sizeof c) != sizeof c) perror_with_name (("read")); /* Set the initial event mask. */ memset (&tte, 0, sizeof (tte)); tte.tte_events |= TTEVT_EXEC | TTEVT_EXIT | TTEVT_FORK | TTEVT_VFORK; tte.tte_events |= TTEVT_LWP_CREATE | TTEVT_LWP_EXIT | TTEVT_LWP_TERMINATE; #ifdef TTEVT_BPT_SSTEP tte.tte_events |= TTEVT_BPT_SSTEP; #endif tte.tte_opts |= TTEO_PROC_INHERIT; if (ttrace (TT_PROC_SET_EVENT_MASK, pid, 0, (uintptr_t)&tte, sizeof tte, 0) == -1) perror_with_name (("ttrace")); /* Tell our child that we have set the initial event mask. */ if (write (inf_ttrace_pfd2[1], &c, sizeof c) != sizeof c) perror_with_name (("write")); do_cleanups (old_chain); push_target (ttrace_ops_hack); /* On some targets, there must be some explicit synchronization between the parent and child processes after the debugger forks, and before the child execs the debuggee program. This call basically gives permission for the child to exec. */ target_acknowledge_created_inferior (pid); /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h, and will be 1 or 2 depending on whether we're starting without or with a shell. */ startup_inferior (START_INFERIOR_TRAPS_EXPECTED); /* On some targets, there must be some explicit actions taken after the inferior has been started up. */ target_post_startup_inferior (pid_to_ptid (pid)); } static void inf_ttrace_create_inferior (char *exec_file, char *allargs, char **env, int from_tty) { gdb_assert (inf_ttrace_num_lwps == 0); gdb_assert (inf_ttrace_num_lwps_in_syscall == 0); gdb_assert (inf_ttrace_page_dict.count == 0); gdb_assert (inf_ttrace_reenable_page_protections == 0); gdb_assert (inf_ttrace_vfork_ppid == -1); fork_inferior (exec_file, allargs, env, inf_ttrace_me, inf_ttrace_him, inf_ttrace_prepare, NULL); } static void inf_ttrace_mourn_inferior (void) { const int num_buckets = ARRAY_SIZE (inf_ttrace_page_dict.buckets); int bucket; inf_ttrace_num_lwps = 0; inf_ttrace_num_lwps_in_syscall = 0; for (bucket = 0; bucket < num_buckets; bucket++) { struct inf_ttrace_page *page; struct inf_ttrace_page *next; page = inf_ttrace_page_dict.buckets[bucket].next; while (page) { next = page->next; xfree (page); page = next; } } inf_ttrace_page_dict.count = 0; unpush_target (ttrace_ops_hack); generic_mourn_inferior (); } static void inf_ttrace_attach (char *args, int from_tty) { char *exec_file; pid_t pid; char *dummy; ttevent_t tte; struct inferior *inf; if (!args) error_no_arg (_("process-id to attach")); dummy = args; pid = strtol (args, &dummy, 0); if (pid == 0 && args == dummy) error (_("Illegal process-id: %s."), args); if (pid == getpid ()) /* Trying to masturbate? */ error (_("I refuse to debug myself!")); if (from_tty) { exec_file = get_exec_file (0); if (exec_file) printf_unfiltered (_("Attaching to program: %s, %s\n"), exec_file, target_pid_to_str (pid_to_ptid (pid))); else printf_unfiltered (_("Attaching to %s\n"), target_pid_to_str (pid_to_ptid (pid))); gdb_flush (gdb_stdout); } gdb_assert (inf_ttrace_num_lwps == 0); gdb_assert (inf_ttrace_num_lwps_in_syscall == 0); gdb_assert (inf_ttrace_vfork_ppid == -1); if (ttrace (TT_PROC_ATTACH, pid, 0, TT_KILL_ON_EXIT, TT_VERSION, 0) == -1) perror_with_name (("ttrace")); inf = add_inferior (pid); inf->attach_flag = 1; /* Set the initial event mask. */ memset (&tte, 0, sizeof (tte)); tte.tte_events |= TTEVT_EXEC | TTEVT_EXIT | TTEVT_FORK | TTEVT_VFORK; tte.tte_events |= TTEVT_LWP_CREATE | TTEVT_LWP_EXIT | TTEVT_LWP_TERMINATE; #ifdef TTEVT_BPT_SSTEP tte.tte_events |= TTEVT_BPT_SSTEP; #endif tte.tte_opts |= TTEO_PROC_INHERIT; if (ttrace (TT_PROC_SET_EVENT_MASK, pid, 0, (uintptr_t)&tte, sizeof tte, 0) == -1) perror_with_name (("ttrace")); push_target (ttrace_ops_hack); /* We'll bump inf_ttrace_num_lwps up and add the private data to the thread as soon as we get to inf_ttrace_wait. At this point, we don't have lwpid info yet. */ inferior_ptid = pid_to_ptid (pid); add_thread_silent (inferior_ptid); } static void inf_ttrace_detach (char *args, int from_tty) { pid_t pid = ptid_get_pid (inferior_ptid); int sig = 0; if (from_tty) { char *exec_file = get_exec_file (0); if (exec_file == 0) exec_file = ""; printf_unfiltered (_("Detaching from program: %s, %s\n"), exec_file, target_pid_to_str (pid_to_ptid (pid))); gdb_flush (gdb_stdout); } if (args) sig = atoi (args); /* ??? The HP-UX 11.0 ttrace(2) manual page doesn't mention that we can pass a signal number here. Does this really work? */ if (ttrace (TT_PROC_DETACH, pid, 0, 0, sig, 0) == -1) perror_with_name (("ttrace")); if (inf_ttrace_vfork_ppid != -1) { if (ttrace (TT_PROC_DETACH, inf_ttrace_vfork_ppid, 0, 0, 0, 0) == -1) perror_with_name (("ttrace")); inf_ttrace_vfork_ppid = -1; } inf_ttrace_num_lwps = 0; inf_ttrace_num_lwps_in_syscall = 0; inferior_ptid = null_ptid; detach_inferior (pid); unpush_target (ttrace_ops_hack); } static void inf_ttrace_kill (void) { pid_t pid = ptid_get_pid (inferior_ptid); if (pid == 0) return; if (ttrace (TT_PROC_EXIT, pid, 0, 0, 0, 0) == -1) perror_with_name (("ttrace")); /* ??? Is it necessary to call ttrace_wait() here? */ if (inf_ttrace_vfork_ppid != -1) { if (ttrace (TT_PROC_DETACH, inf_ttrace_vfork_ppid, 0, 0, 0, 0) == -1) perror_with_name (("ttrace")); inf_ttrace_vfork_ppid = -1; } target_mourn_inferior (); } /* Check is a dying thread is dead by now, and delete it from GDBs thread list if so. */ static int inf_ttrace_delete_dead_threads_callback (struct thread_info *info, void *arg) { lwpid_t lwpid; struct inf_ttrace_private_thread_info *p; if (is_exited (info->ptid)) return 0; lwpid = ptid_get_lwp (info->ptid); p = (struct inf_ttrace_private_thread_info *) info->private; /* Check if an lwp that was dying is still there or not. */ if (p->dying && (kill (lwpid, 0) == -1)) /* It's gone now. */ delete_thread (info->ptid); return 0; } /* Resume the lwp pointed to by INFO, with REQUEST, and pass it signal SIG. */ static void inf_ttrace_resume_lwp (struct thread_info *info, ttreq_t request, int sig) { pid_t pid = ptid_get_pid (info->ptid); lwpid_t lwpid = ptid_get_lwp (info->ptid); if (ttrace (request, pid, lwpid, TT_NOPC, sig, 0) == -1) { struct inf_ttrace_private_thread_info *p = (struct inf_ttrace_private_thread_info *) info->private; if (p->dying && errno == EPROTO) /* This is expected, it means the dying lwp is really gone by now. If ttrace had an event to inform the debugger the lwp is really gone, this wouldn't be needed. */ delete_thread (info->ptid); else /* This was really unexpected. */ perror_with_name (("ttrace")); } } /* Callback for iterate_over_threads. */ static int inf_ttrace_resume_callback (struct thread_info *info, void *arg) { if (!ptid_equal (info->ptid, inferior_ptid) && !is_exited (info->ptid)) inf_ttrace_resume_lwp (info, TT_LWP_CONTINUE, 0); return 0; } static void inf_ttrace_resume (ptid_t ptid, int step, enum target_signal signal) { int resume_all; ttreq_t request = step ? TT_LWP_SINGLE : TT_LWP_CONTINUE; int sig = target_signal_to_host (signal); struct thread_info *info; /* A specific PTID means `step only this process id'. */ resume_all = (ptid_equal (ptid, minus_one_ptid)); /* If resuming all threads, it's the current thread that should be handled specially. */ if (resume_all) ptid = inferior_ptid; info = find_thread_pid (ptid); inf_ttrace_resume_lwp (info, request, sig); if (resume_all) /* Let all the other threads run too. */ iterate_over_threads (inf_ttrace_resume_callback, NULL); } static ptid_t inf_ttrace_wait (ptid_t ptid, struct target_waitstatus *ourstatus) { pid_t pid = ptid_get_pid (ptid); lwpid_t lwpid = ptid_get_lwp (ptid); ttstate_t tts; struct thread_info *ti; ptid_t related_ptid; /* Until proven otherwise. */ ourstatus->kind = TARGET_WAITKIND_SPURIOUS; if (pid == -1) pid = lwpid = 0; gdb_assert (pid != 0 || lwpid == 0); do { set_sigint_trap (); set_sigio_trap (); if (ttrace_wait (pid, lwpid, TTRACE_WAITOK, &tts, sizeof tts) == -1) perror_with_name (("ttrace_wait")); if (tts.tts_event == TTEVT_VFORK && tts.tts_u.tts_fork.tts_isparent) { if (inf_ttrace_vfork_ppid != -1) { gdb_assert (inf_ttrace_vfork_ppid == tts.tts_pid); if (ttrace (TT_PROC_DETACH, tts.tts_pid, 0, 0, 0, 0) == -1) perror_with_name (("ttrace")); inf_ttrace_vfork_ppid = -1; } tts.tts_event = TTEVT_NONE; } clear_sigio_trap (); clear_sigint_trap (); } while (tts.tts_event == TTEVT_NONE); /* Now that we've waited, we can re-enable the page protections. */ if (inf_ttrace_reenable_page_protections) { gdb_assert (inf_ttrace_num_lwps_in_syscall == 0); inf_ttrace_enable_page_protections (tts.tts_pid); inf_ttrace_reenable_page_protections = 0; } ptid = ptid_build (tts.tts_pid, tts.tts_lwpid, 0); if (inf_ttrace_num_lwps == 0) { struct thread_info *ti; inf_ttrace_num_lwps = 1; /* This is the earliest we hear about the lwp member of INFERIOR_PTID, after an attach or fork_inferior. */ gdb_assert (ptid_get_lwp (inferior_ptid) == 0); /* We haven't set the private member on the main thread yet. Do it now. */ ti = find_thread_pid (inferior_ptid); gdb_assert (ti != NULL && ti->private == NULL); ti->private = xmalloc (sizeof (struct inf_ttrace_private_thread_info)); memset (ti->private, 0, sizeof (struct inf_ttrace_private_thread_info)); /* Notify the core that this ptid changed. This changes inferior_ptid as well. */ thread_change_ptid (inferior_ptid, ptid); } switch (tts.tts_event) { #ifdef TTEVT_BPT_SSTEP case TTEVT_BPT_SSTEP: /* Make it look like a breakpoint. */ ourstatus->kind = TARGET_WAITKIND_STOPPED; ourstatus->value.sig = TARGET_SIGNAL_TRAP; break; #endif case TTEVT_EXEC: ourstatus->kind = TARGET_WAITKIND_EXECD; ourstatus->value.execd_pathname = xmalloc (tts.tts_u.tts_exec.tts_pathlen + 1); if (ttrace (TT_PROC_GET_PATHNAME, tts.tts_pid, 0, (uintptr_t)ourstatus->value.execd_pathname, tts.tts_u.tts_exec.tts_pathlen, 0) == -1) perror_with_name (("ttrace")); ourstatus->value.execd_pathname[tts.tts_u.tts_exec.tts_pathlen] = 0; /* At this point, all inserted breakpoints are gone. Doing this as soon as we detect an exec prevents the badness of deleting a breakpoint writing the current "shadow contents" to lift the bp. That shadow is NOT valid after an exec. */ mark_breakpoints_out (); break; case TTEVT_EXIT: store_waitstatus (ourstatus, tts.tts_u.tts_exit.tts_exitcode); inf_ttrace_num_lwps = 0; break; case TTEVT_FORK: related_ptid = ptid_build (tts.tts_u.tts_fork.tts_fpid, tts.tts_u.tts_fork.tts_flwpid, 0); ourstatus->kind = TARGET_WAITKIND_FORKED; ourstatus->value.related_pid = related_ptid; /* Make sure the other end of the fork is stopped too. */ if (ttrace_wait (tts.tts_u.tts_fork.tts_fpid, tts.tts_u.tts_fork.tts_flwpid, TTRACE_WAITOK, &tts, sizeof tts) == -1) perror_with_name (("ttrace_wait")); gdb_assert (tts.tts_event == TTEVT_FORK); if (tts.tts_u.tts_fork.tts_isparent) { related_ptid = ptid_build (tts.tts_u.tts_fork.tts_fpid, tts.tts_u.tts_fork.tts_flwpid, 0); ptid = ptid_build (tts.tts_pid, tts.tts_lwpid, 0); ourstatus->value.related_pid = related_ptid; } break; case TTEVT_VFORK: gdb_assert (!tts.tts_u.tts_fork.tts_isparent); related_ptid = ptid_build (tts.tts_u.tts_fork.tts_fpid, tts.tts_u.tts_fork.tts_flwpid, 0); ourstatus->kind = TARGET_WAITKIND_VFORKED; ourstatus->value.related_pid = related_ptid; /* HACK: To avoid touching the parent during the vfork, switch away from it. */ inferior_ptid = ptid; break; case TTEVT_LWP_CREATE: lwpid = tts.tts_u.tts_thread.tts_target_lwpid; ptid = ptid_build (tts.tts_pid, lwpid, 0); ti = add_thread (ptid); ti->private = xmalloc (sizeof (struct inf_ttrace_private_thread_info)); memset (ti->private, 0, sizeof (struct inf_ttrace_private_thread_info)); inf_ttrace_num_lwps++; ptid = ptid_build (tts.tts_pid, tts.tts_lwpid, 0); /* Let the lwp_create-caller thread continue. */ ttrace (TT_LWP_CONTINUE, ptid_get_pid (ptid), ptid_get_lwp (ptid), TT_NOPC, 0, 0); /* Return without stopping the whole process. */ ourstatus->kind = TARGET_WAITKIND_IGNORE; return ptid; case TTEVT_LWP_EXIT: if (print_thread_events) printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (ptid)); ti = find_thread_pid (ptid); gdb_assert (ti != NULL); ((struct inf_ttrace_private_thread_info *)ti->private)->dying = 1; inf_ttrace_num_lwps--; /* Let the thread really exit. */ ttrace (TT_LWP_CONTINUE, ptid_get_pid (ptid), ptid_get_lwp (ptid), TT_NOPC, 0, 0); /* Return without stopping the whole process. */ ourstatus->kind = TARGET_WAITKIND_IGNORE; return ptid; case TTEVT_LWP_TERMINATE: lwpid = tts.tts_u.tts_thread.tts_target_lwpid; ptid = ptid_build (tts.tts_pid, lwpid, 0); if (print_thread_events) printf_unfiltered(_("[%s has been terminated]\n"), target_pid_to_str (ptid)); ti = find_thread_pid (ptid); gdb_assert (ti != NULL); ((struct inf_ttrace_private_thread_info *)ti->private)->dying = 1; inf_ttrace_num_lwps--; /* Resume the lwp_terminate-caller thread. */ ptid = ptid_build (tts.tts_pid, tts.tts_lwpid, 0); ttrace (TT_LWP_CONTINUE, ptid_get_pid (ptid), ptid_get_lwp (ptid), TT_NOPC, 0, 0); /* Return without stopping the whole process. */ ourstatus->kind = TARGET_WAITKIND_IGNORE; return ptid; case TTEVT_SIGNAL: ourstatus->kind = TARGET_WAITKIND_STOPPED; ourstatus->value.sig = target_signal_from_host (tts.tts_u.tts_signal.tts_signo); break; case TTEVT_SYSCALL_ENTRY: gdb_assert (inf_ttrace_reenable_page_protections == 0); inf_ttrace_num_lwps_in_syscall++; if (inf_ttrace_num_lwps_in_syscall == 1) { /* A thread has just entered a system call. Disable any page protections as the kernel can't deal with them. */ inf_ttrace_disable_page_protections (tts.tts_pid); } ourstatus->kind = TARGET_WAITKIND_SYSCALL_ENTRY; ourstatus->value.syscall_id = tts.tts_scno; break; case TTEVT_SYSCALL_RETURN: if (inf_ttrace_num_lwps_in_syscall > 0) { /* If the last thread has just left the system call, this would be a logical place to re-enable the page protections, but that doesn't work. We can't re-enable them until we've done another wait. */ inf_ttrace_reenable_page_protections = (inf_ttrace_num_lwps_in_syscall == 1); inf_ttrace_num_lwps_in_syscall--; } ourstatus->kind = TARGET_WAITKIND_SYSCALL_RETURN; ourstatus->value.syscall_id = tts.tts_scno; break; default: gdb_assert (!"Unexpected ttrace event"); break; } /* Make sure all threads within the process are stopped. */ if (ttrace (TT_PROC_STOP, tts.tts_pid, 0, 0, 0, 0) == -1) perror_with_name (("ttrace")); /* Now that the whole process is stopped, check if any dying thread is really dead by now. If a dying thread is still alive, it will be stopped too, and will still show up in `info threads', tagged with "(Exiting)". We could make `info threads' prune dead threads instead via inf_ttrace_thread_alive, but doing this here has the advantage that a frontend is notificed sooner of thread exits. Note that a dying lwp is still alive, it still has to be resumed, like any other lwp. */ iterate_over_threads (inf_ttrace_delete_dead_threads_callback, NULL); return ptid; } /* Transfer LEN bytes from ADDR in the inferior's memory into READBUF, and transfer LEN bytes from WRITEBUF into the inferior's memory at ADDR. Either READBUF or WRITEBUF may be null, in which case the corresponding transfer doesn't happen. Return the number of bytes actually transferred (which may be zero if an error occurs). */ static LONGEST inf_ttrace_xfer_memory (CORE_ADDR addr, ULONGEST len, void *readbuf, const void *writebuf) { pid_t pid = ptid_get_pid (inferior_ptid); /* HP-UX treats text space and data space differently. GDB however, doesn't really know the difference. Therefore we try both. Try text space before data space though because when we're writing into text space the instruction cache might need to be flushed. */ if (readbuf && ttrace (TT_PROC_RDTEXT, pid, 0, addr, len, (uintptr_t)readbuf) == -1 && ttrace (TT_PROC_RDDATA, pid, 0, addr, len, (uintptr_t)readbuf) == -1) return 0; if (writebuf && ttrace (TT_PROC_WRTEXT, pid, 0, addr, len, (uintptr_t)writebuf) == -1 && ttrace (TT_PROC_WRDATA, pid, 0, addr, len, (uintptr_t)writebuf) == -1) return 0; return len; } static LONGEST inf_ttrace_xfer_partial (struct target_ops *ops, enum target_object object, const char *annex, gdb_byte *readbuf, const gdb_byte *writebuf, ULONGEST offset, LONGEST len) { switch (object) { case TARGET_OBJECT_MEMORY: return inf_ttrace_xfer_memory (offset, len, readbuf, writebuf); case TARGET_OBJECT_UNWIND_TABLE: return -1; case TARGET_OBJECT_AUXV: return -1; case TARGET_OBJECT_WCOOKIE: return -1; default: return -1; } } /* Print status information about what we're accessing. */ static void inf_ttrace_files_info (struct target_ops *ignore) { struct inferior *inf = current_inferior (); printf_filtered (_("\tUsing the running image of %s %s.\n"), inf->attach_flag ? "attached" : "child", target_pid_to_str (inferior_ptid)); } static int inf_ttrace_thread_alive (ptid_t ptid) { return 1; } /* Return a string describing the state of the thread specified by INFO. */ static char * inf_ttrace_extra_thread_info (struct thread_info *info) { struct inf_ttrace_private_thread_info* private = (struct inf_ttrace_private_thread_info *) info->private; if (private != NULL && private->dying) return "Exiting"; return NULL; } static char * inf_ttrace_pid_to_str (ptid_t ptid) { pid_t pid = ptid_get_pid (ptid); lwpid_t lwpid = ptid_get_lwp (ptid); static char buf[128]; if (lwpid == 0) xsnprintf (buf, sizeof buf, "process %ld", (long) pid); else xsnprintf (buf, sizeof buf, "process %ld, lwp %ld", (long) pid, (long) lwpid); return buf; } struct target_ops * inf_ttrace_target (void) { struct target_ops *t = inf_child_target (); t->to_attach = inf_ttrace_attach; t->to_detach = inf_ttrace_detach; t->to_resume = inf_ttrace_resume; t->to_wait = inf_ttrace_wait; t->to_files_info = inf_ttrace_files_info; t->to_can_use_hw_breakpoint = inf_ttrace_can_use_hw_breakpoint; t->to_insert_watchpoint = inf_ttrace_insert_watchpoint; t->to_remove_watchpoint = inf_ttrace_remove_watchpoint; t->to_stopped_by_watchpoint = inf_ttrace_stopped_by_watchpoint; t->to_region_ok_for_hw_watchpoint = inf_ttrace_region_ok_for_hw_watchpoint; t->to_kill = inf_ttrace_kill; t->to_create_inferior = inf_ttrace_create_inferior; t->to_follow_fork = inf_ttrace_follow_fork; t->to_mourn_inferior = inf_ttrace_mourn_inferior; t->to_thread_alive = inf_ttrace_thread_alive; t->to_extra_thread_info = inf_ttrace_extra_thread_info; t->to_pid_to_str = inf_ttrace_pid_to_str; t->to_xfer_partial = inf_ttrace_xfer_partial; ttrace_ops_hack = t; return t; } #endif /* Prevent warning from -Wmissing-prototypes. */ void _initialize_hppa_hpux_nat (void); void _initialize_inf_ttrace (void) { #ifdef HAVE_TTRACE inf_ttrace_page_dict.pagesize = getpagesize(); #endif }